Mapping service components in a broadcast environment

ABSTRACT

Services and service components in a broadcast network may be mapped to disparate physical layer transmission channels (PLPs) using logical layer pipes (LLPs). The use of LLPs allows different service components of a single service to be mapped to physical layer transmission channels (PLPs). Accordingly, service components may be shared among different services. Additionally or alternatively, different functions (e.g., different error detection or correction protocols) may be applied to each service components of a service. A receiver may identify services, service components and corresponding PLPs based on LLP identifiers. The receiver may then access and receive desired services and service components through the identified PLPs.

BACKGROUND

Content and other services broadcast in a network may often include manyservice components. For example, a high definition video may include astandard definition component that provides a base amount of contentdata and a high definition component that supplements the base contentdata with high definition information. In current broadcast protocols,such service components are mapped to and carried in a physicallayer—according to e.g. the OSI model—through pipes. A physical layerpipe provides a transmission channel through which a sender may transmitdata as raw bits to one or more receiving devices. However, currentprotocols require that all service components of a given service bemapped to the same pipe. Accordingly, components cannot be sharedbetween different services, increasing the resources necessary tobroadcast multiple services at once. Additionally, requiring thatservice components be mapped to the same pipe can inhibit differentfunctions such as error correction or error protection at differentstrengths from being applied to different components.

BRIEF SUMMARY

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter.

One or more aspects relate to a signaling structure for broadcasttransmissions in which services or service components thereof are mappedto multiple physical layer transmission channels (PLP) through logicallayer pipes. Logical layer pipes (LLP) are associated with either theservice or service components or both as well as a set of one or morePLPs to which the service components are mapped. By using LLPs,different services may share service components by associating each LLP,corresponding to each of the different services, with the PLPcorresponding to the service component to be shared. Additionally, theuse of an LLP allows for different service components of a service to bemapped to different PLPs. Accordingly, for example different errorcorrection or error detection protocols may be applied to the differentservice components if needed.

According to another aspect, a receiver or subscriber of a broadcastservice may discover PLPs through the use of an LLP. For example, areceiver may initially receive a broadcast service signal advertisingone or more services. The receiver may then determine services availablein the broadcast along with LLPs associated therewith. Upon selection ofone of the services or service components, the receiver may discover thePLPs of the service components for the selected service using the LLPs.Once discovered, the PLPs may be used to access the service componentsof the selected service.

According to yet another aspect, LLPs may be implemented in a signalinglayer of a broadcast protocol. The signaling layer may include LLPdefinition information as well as PLP data.

According to another aspect, LLPs may be implemented in an adaptationlayer, which may correspond e.g. to layer 2 of the Open SystemsInterconnection (OSI) Reference model. In one example, an LLP may bedefined in the adaptation layer and associated with a correspondingservice and set of PLPs. In another example, an LLP may be defined in asignaling layer while a mapping component is specified in the adaptationlayer. The mapping component is configured to map a service component tothe corresponding LLP. Each service component in a service may be linkedor otherwise associated to a distinct mapping component. The mappingcomponents may then be associated with a single LLP.

According to yet another aspect, a broadcast system may establish asignaling structure using LLPs to associate services and servicecomponents to PLPs. The broadcast system may then broadcast availableservices to receiving devices along with the LLP and PLP information.The receiving devices may then access services and their associatedservice components by discovering PLP information through acorresponding LLP.

BRIEF DESCRIPTION OF THE DRAWINGS

Certain embodiments are illustrated by way of example and not limited inthe accompanying figures in which like reference numerals indicatesimilar elements and in which:

FIG. 1 is a block diagram of an example communication network in whichone or more embodiments may be implemented.

FIG. 2 is a block diagram of an example communication device accordingto one or more aspects described herein.

FIG. 3 illustrates an example data model for network transmissionsaccording to one or more aspects described herein.

FIG. 4 illustrates a broadcast network in which services and servicecomponents are transmitted using physical layer transmission channelsaccording to one or more aspects described herein.

FIGS. 5 and 6 illustrate example signaling protocols and structuresusing logical layer pipes to associate services and service componentsto physical layer transmission channels according to one or more aspectsdescribed herein.

FIGS. 7-10 illustrate example signaling configurations for broadcastingvarious services according to one or more aspects described herein.

FIG. 11 illustrates an example receiver buffer for receiving andconsuming logical layer pipe information according to one or moreaspects described herein.

FIG. 12 illustrates an example transmission of LLP frames in an LLPaccording to one or more aspects described herein.

FIGS. 13 and 14 illustrate example transmission configurations in whichan LLP frame and associated PLP frames are transmitted according to adigital video broadcast protocol.

FIG. 15 illustrates an example signaling structure for linking a serviceto an LLP according to one or more aspects described herein.

FIG. 16 illustrates example identifier types according to one or moreaspects described herein.

FIGS. 17-19 illustrate layered data models according to one or moreaspects described herein.

FIG. 20 illustrates a signaling structure for associating PLPs to LLPsaccording to one or more aspects described herein.

FIG. 21 illustrates an example method for receiving and accessing aservice according to one or more aspects described herein.

FIG. 22 illustrates an example method for establishing a signalingprotocol and structure for broadcasting a service and associated servicecomponents according to one or more aspects described herein.

FIG. 23 illustrates an example cylic redundancy check (CRC) decoderaccording to one or more aspects described herein.

DETAILED DESCRIPTION

In the following description of the various embodiments, reference ismade to the accompanying drawings, which form a part hereof, and inwhich are shown by way of illustration various embodiments in which theinvention may be practiced. It is to be understood that otherembodiments may be utilized and structural and functional modificationsmay be made without departing from the scope of the present invention.

FIG. 1 illustrates an example communication network through whichvarious inventive principles may be practiced. A number of computers anddevices including mobile communication device 105, mobile phone 110,personal digital assistant (PDA) or mobile computer 120, personalcomputer (PC) 115, service provider 125 and content provider 130 maycommunicate with one another and with other devices through network 100.Network 100 may include wired and wireless connections and networkelements, and connections over the network may include permanent ortemporary connections. Communication through network 100 is not limitedto the illustrated devices and may include additional mobile or fixeddevices such as a video storage system, an audio/video player, a digitalcamera/camcorder, a positioning device such as a GPS (Global PositioningSystem) device or satellite, a television, an audio/video player, aradio broadcasting receiver, a set-top box (STB), a digital videorecorder, remote control devices and any combination thereof.

Although shown as a single network in FIG. 1 for simplicity, network 100may include multiple networks that are interlinked so as to provideinternetworked communications. Such networks may include one or moreprivate or public packet-switched networks, e.g. the Internet, one ormore private or public circuit-switched networks, e.g. a public switchedtelephone network, a cellular network configured to facilitatecommunications to and from mobile communication devices 105 and 110,e.g. through use of base stations, mobile switching centers, etc., ashort or medium range wireless communication connection, e.g.Bluetooth®, ultra wideband (UWB), infrared, WiBree, wireless local areanetwork (WLAN) according to one or more versions of Institute ofElectrical and Electronics Engineers (IEEE) standard no. 802.11), or ahigh-speed wireless data network such as Evolution-Data Optimized(EV-DO) networks, Universal Mobile Telecommunications System (UMTS)networks, Long Term Evolution (LTE) networks or Enhanced Data rates forGSM Evolution (EDGE) networks. Devices 105-120 may use variouscommunication protocols such as Internet Protocol (IP), TransmissionControl Protocol (TCP), Simple Mail Transfer Protocol (SMTP) amongothers known in the art. Various messaging services such as ShortMessaging Service (SMS) and/or Multimedia Message Service (MMS) may alsobe included.

Devices 105-120 may be configured to interact with each other or otherdevices, such as content server 130 or service provider 125. In oneexample, mobile device 110 may include client software 165 that isconfigured to coordinate the transmission and reception of informationto and from content provider/server 130. In one arrangement, clientsoftware 165 may include application or server specific protocols forrequesting and receiving content from content server 130. For example,client software 165 may comprise a Web browser or mobile variantsthereof and content provider/server 130 may comprise a web server.Billing services (not shown) may also be included to charge access ordata fees for services rendered. In one arrangement where serviceprovider 125 provides cellular network access, e.g. acts as a wirelessservice provider, client software 165 may include instructions foraccess and communication through the cellular network. Client software165 may be stored in computer-readable memory 160 such as read only,random access memory, writeable and rewriteable media and removablemedia in device 110 and may include instructions that cause one or morecomponents—e.g., processor 155, a transceiver, and a display—of device110 to perform various functions and methods including those describedherein.

FIG. 2 illustrates an example computing device such as mobile device 212that may be used in network 100 of FIG. 1. Mobile device 212 may includea controller 225 connected to a user interface control 230, display 236and other elements as illustrated. Controller 225 may include one ormore processors 228 and memory 234 storing software 240, e.g. clientsoftware 165. Mobile device 212 may also include a battery 250, speaker252 and antenna 254. User interface control 230 may include controllersor adapters configured to receive input from or provide output to akeypad, touch screen, voice interface—e.g. via microphone 256, functionkeys, joystick, data glove, mouse and the like.

Computer executable instructions and data used by processor 228 andother components of mobile device 212 may be stored in a storagefacility such as memory 234. Memory 234 may comprise any type orcombination of read only memory (ROM) modules or random access memory(RAM) modules, including both volatile and nonvolatile memory such asdisks. Software 240 may be stored within memory 234 to provideinstructions to processor 228 such that when the instructions areexecuted, processor 228, mobile device 212 and/or other components ofmobile device 212 are caused to perform various functions or methodssuch as those described herein. Software may include both applicationsand operating system software, and may include code segments,instructions, applets, pre-compiled code, compiled code, computerprograms, program modules, engines, program logic, and combinationsthereof. Computer executable instructions and data may further be storedon computer readable media including electrically erasable programmableread-only memory (EEPROM), flash memory or other memory technology,CD-ROM, DVD or other optical disk storage, magnetic cassettes, magnetictape, magnetic storage and the like.

Mobile device 212 or its various components may be configured toreceive, decode and process various types of transmissions includingdigital broadband broadcast transmissions that are based, for example,on the Digital Video Broadcast (DVB) standard, such as DVB-H, DVB-H+, orDVB-MHP, through a specific broadcast transceiver 241. Other digitaltransmission formats may alternatively be used to deliver content andinformation regarding availability of supplemental services.Additionally or alternatively, mobile device 212 may be configured toreceive, decode and process transmissions through FM/AM Radiotransceiver 242, wireless local area network (WLAN) transceiver 243, andtelecommunications transceiver 244. Transceivers 241, 242, 243 and 244may, alternatively, include individual transmitter and receivercomponents.

Although the above description of FIG. 2 generally relates to a mobiledevice, other devices or systems may include the same or similarcomponents and perform the same or similar functions and methods. Forexample, a stationary computer such as PC 115 (FIG. 1) may include thecomponents or a subset of the components described above and may beconfigured to perform the same or similar functions as mobile device 212and its components.

According to some digital video broadcasting protocols, components thatmake up a particular service like a content program or an interactivefunction are mapped through a physical layer pipe (PLP). A physicallayer, as used herein, generally refers to a portion of a networkprotocol that is configured to define hardware-specific operations foreffecting the transmission or reception of electronic signals over adata network. The Open Systems Interconnection (OSI) Reference Model,for example, provides for a layered communication architecture includinga physical layer. FIG. 3 illustrates one representation of an OSIReference Model.

A PLP generally refers to a transmission channel between a source and adestination node defined at the physical layer level. The physical layerrefers to a low level layer, often the lowest layer, in a protocol stackthat is configured to facilitate the transmission of raw bits from asource to a destination. The physical layer may be configured to specifyfrequencies, voltages, bit rates and the like for transmission of data.The physical layer may define multiple channels—pipes—through which rawbits representative of the data such as broadcast data may be sent. Forexample, different broadcast services and data associated therewith maybe mapped to different physical layer pipes and made availabletherethrough. Accordingly, the physical layer may be configured toidentify the appropriate transmission channel for a series of bitscorresponding to a particular service and transmit the data through theidentified channel or pipe. In a broadcast arrangement, a PLP may beestablished between a source and multiple destinations. In one example,a PLP may correspond to a physical layer time-division multiplexedchannel that is carried by specified sub-slices of a transmission stream(e.g., DVB-T2 stream). When an end-user device wishes to access acomponent of a particular service, the end-user device may identify thecorresponding PLP or PLPs and access the service data therethrough. Inthe broadcast scenario, a receiving device may listen for the particularsub-slices corresponding to the PLP or PLPs carrying the desired serviceor services.

FIG. 4 illustrates a broadcast network in which services and servicecomponents, e.g. content provided from content servers 411, aretransmitted through multiple PLPs 401 from a broadcast system 400, whereeach of the PLPs 401 are configured to carry a different broadcastservice component, e.g., components 403. PLPs 401 may be defined assegments of a transmission stream 409 that together make up atransmission channel for a particular one of service components 403.Each of components 403 may be mapped to a different one of PLPs 401 toprovide the ability to share service components 403 across services.Alternatively or additionally, two components may be mapped to the samepipe depending on a desired configuration (not shown).

Pipes 401 corresponding to components of a single service may beidentified by combining PLPs 401 into a logical grouping 407—into alogical layer pipe—that is associated with a service. Logical layerpipes (LLP) generally refer to logical associations such as mappingsthat link a service or service components to a PLP. LLPs may be definedusing various data structures such as tables, lists and the like. PLPs401 may be identified for accessing components 403 of a service bydetermining the logical grouping or LLP 407 associated with that serviceand examining PLP parameters specified thereby. In one example, LLP 407may be identified in a service descriptor configured to advertiseavailable services to network devices 405—cell phone 405 a, computer 405b and set-top box 405 c. LLP identification information may be carriedin a packet header of the broadcast transmission stream 409.Alternatively or additionally, LLP information—e.g. LLP identifiers—foreach service may be specified in electronic service guide data. Thus,upon receiving the packet header and/or electronic service guide data, areceiving device such as cell phone 405 a may extract LLP information toidentify components of a service and their associated PLPs. LLPsignaling is described in further detail herein.

Current PLP architectures and data models generally require that allservice components for a service be mapped to a single PLP. Accordingly,the sharing of a service component among multiple services and theapplication of different functionalities to different service componentsof a single service, e.g., in scenarios where functionalities areapplied on a per-PLP basis, might not be possible. For example, theseparate layers of a Scalable Video Codec (SVC) may be configured asdifferent components of a service, each layer of the SVC being mapped tothe same PLP. Because the layers of the service are mapped to the samePLP, it might not be possible to apply different functionalities such aserror detection or correction to each separate layer of the SVC becausethe functionalities might generally be applied across an entire PLP, notfor each service component in a PLP. Furthermore, in a scenario or adata model requiring mapping all service components for a service to asingle PLP, it may not be possible to receive only a subset of theservice components of a service. As an example, a service may comprise avideo component, and two audio components in different languages, allmapped to a single PLP. Because the both audio components—providingsimilar information in different languages—are mapped to the same PLP,it might not be possible to receive only one of the audio components.

FIG. 5 illustrates an example broadcasting protocol in which componentsof a service may be distributed in different PLPs, thereby allowingsharing of service components and the application of differentfunctionalities to different components of a single service.Broadcasting protocol 501 includes an electronic service guide (ESG)layer 503 as well as one or more additional layers 505. The additionallayer 505 of protocol 501 may include a physical layer that provides oneor more PLPs 507 to which service components 511 for a service 515advertised in an ESG of ESG layer 503 are mapped. The mapping of theservice components to the disparate PLPs 507 is facilitated by a logicallayer pipe (LLP) 513. In one example, an LLP such as LLP 513 may definea mapping between a service, e.g. service 515, or service component,e.g. service components 511, and one or more PLPs, e.g. PLPs 507.Accordingly, by using LLPs to define relationships between services orservice components and PLPs, service components of a single service maybe mapped to a set of more than one PLP. The mapping facilitated by theLLP may further allow service components of a single service to bemapped to disparate PLPs.

As illustrated in FIG. 5, LLP 513 maps the set of service components 511corresponding to service 515 to PLPs 507. For example, service component511 a and 511 c may be mapped to PLP 507 b, while service component 511b may be mapped to PLP 507 a. In such a configuration, a receivingdevice may discover the service components 511 through service 515 andsubsequently identify a set of corresponding PLPs 507 carryingcomponents 511 using the mapping provided by LLP 513. For example, atable or other data structure corresponding to LLP 613 may be definedmapping service components 511 to PLPs 507. A separate data structuremay also be defined mapping service components 511 to service 515.

Alternatively, in an example illustrated in FIG. 6, LLP 613 defines anassociation between service 615 and PLPs 607 to which components 611 aremapped. Accordingly, the association or linking of service components611 with LLP 613 and PLPs 607 is configured indirectly through service615. Thus, discovery of PLPs 607 may be conducted through service615—e.g. by, inspecting service parameters for LLP data—rather thanthrough service components 611—as may be the case in the exampleillustrated in FIG. 5. In one example, a structure such as a table maybe defined mapping service 615 to LLP 613 while a separate structure maybe defined for mapping service 615 to service components 611.

FIG. 7 illustrates an example mapping of service components forproviding high definition and standard definition content, e.g. by usinga scalable video codec. A scalable video codec may include standarddefinition (SD) service 701 and high definition (HD) service 703 fordefining different levels of video quality. SD service 701 may comprisea first set of content signals that define a first level of videoquality while HD service 703 may include a second set of signals thatincreases video quality to a second level higher than the first whenadded to the first set of content signals. For example, when a clientrequests HD content, HD service 703 may provide both SD signals and HDsignals associated with the requested content to the client. Quality maybe defined by resolution, refresh rates, frames per second and the like.The SD content may be defined as a SD service component 705 while the HDcontent may be defined as a HD service component 707. Thus, while SDservice 701 might only need SD service component 705, HD service 703 mayrequire access to both SD service component 705 and HD service component707. Instead of having to duplicate SD service component 705 for each ofSD service 701 and HD service 703, LLPs 709 and 711 allow for services701 and 703 to share SD service component 705.

LLPs 709 and 711 are each associated with one or more PLPs 713 and 715.In the illustrated example, SD service component 705 may be mapped toPLP 715, implying that SD content may be accessed through PLP 715, whileHD service component 703 may be mapped to PLP 713, implying that HDcontent may be accessed through PLP 713. Although SD service component705 and HD service component 703 are both parts of HD service 703, theymay be mapped to different PLPs 713 and 715 by using LLPs—e.g. LLPs 709and 711—so that SD service component 705 may be shared. Thus, LLP 709corresponding to SD service 701 may be associated with PLP 715 while LLP711 corresponding to HD service 703 may be associated with PLPs 713 and715. Because shared service components might not need to be duplicatedfor different services, networking, processing and storage resources maybe reduced.

Each of SD and HD services 701 and 703 may be identified by a globalservice identifier that is known in a broadcast network. A device mayrequest a particular service by using the global service identifiercorresponding thereto. A service component such as SD service component705 or HD service component 707, on the other hand, may be defined forexample by one or more sources addresses, destination addresses, sourceports and destination ports. Further, each of LLPs 709 and 711 and PLPs713 and 715 may be assigned an LLP identifier and PLP identifier,respectively.

FIG. 8 illustrates another example mapping of service components to PLPsusing LLP, the example mapping being used to provide a teletext servicein a television broadcast environment. Multiple broadcast channels mayinclude teletext, which can be referenced as a rough version of digitalnewspaper or message board. Usually teletext services cover news,information about television programs, weather information etc. Teletextis used to provide an information service as part of the broadcast. Incurrent systems, a separate teletext service component may be providedfor each broadcast or broadcast service—e.g., channels, interactivefunctions, etc. With many broadcasts or broadcast services usingteletext, additional resources may be needed in the broadcast medium andat the broadcast source. Aspects described herein allow for multiplebroadcast services such as service 801 and service 803 to share ateletext service component 805 while still providing differentadditional service components 807 and 809—e.g., video, audio, images,text. Using LLPs 811 and 813, services 801 and 803, respectively, mayinclude teletext service component 805 by mapping component 805 tocorresponding PLP 815 shared by LLPs 811 and 813.

FIGS. 9 and 10 illustrate additional examples of mapping servicecomponents in other contexts such as multilingual services, asillustrated in FIG. 9, and fast zapping, (as illustrated in FIG. 10).The zapping corresponds to a procedure where an end user switches intoanother channel. Typically end users want this to happen fast. In theexample of multilingual services, FIG. 9 illustrates that a service 901may be associated with a LLP 903 that maps multiple service componentssuch as video 905, Finnish audio 907 and Swedish audio 909 tocorresponding PLPs 911, 913 and 915, respectively. Because servicecomponents 907 and 909 are associated with service 901 despite beingmapped to different PLPs 913 and 915, respectively, service 901 mayallow a user to switch between Swedish or Finnish audio. LLP 903facilitates this process by providing a mapping between service 901 andthe PLPs 911, 913 and 915 associated with each of the service components905, 907 and 909. For example, service 901 may selectively activate oruse one of audio service components 907 and 909 via LLP 903 and PLPs 913and 915 depending on a language selected.

In another example, FIG. 10 illustrates a mapping structure in whichdifferent radio services 1001, 1003 and 1005 including different servicecomponents 1007, 1009 and 1011, respectively, are all linked to a singleLLP 1007. LLP 1007, in turn, maps each of services 1001, 1003 and 1005to all three PLPs 1013, 1015 and 1017, giving each of services 1001,1003 and 1005 to access any of the three different service components1007, 1009 and 1011. Using this configuration, a user subscribed toservice 1003 may access content provided by service component 1007, eventhough service component 1007 is included in service 1001. Switchingbetween content (i.e., zapping) provided by components 1007, 1009 and1011 may also be faster because a user would not have to wait for thecompletion of a subscription process—e.g. to a correspondingservice—prior to obtaining access to requested content. That is,requiring the user to unsubscribe from one service, e.g. service 1003,and subscribe to another service, e.g. service 1001, to access differentcontent may increase the amount of time required to switch betweencontent. Instead, if subscription is required, access to the requestedcontent may be provided in the above described manner while a usercompletes a subscription process.

FIG. 11 illustrates an example receiver buffer model that may be usedfor receiving LLPs. In particular, receiver buffer 1101 is configured toreceive and consume an LLP frame. For example, receive buffer 1101 maybe configured to parse the LLP frame and extract relevant informationsuch as packet header data that defines a structure of the frame—e.g.size of a slice, PLP frames corresponding to service components and thelike. The receiver buffer 1101 may further be configured to determine anamount of time required for consumption of the frame. This value may beprovided as the parameter T_(OUT) _(—) _(LLP). The relevance andapplication of T_(OUT) _(—) _(LLP) is described in further detail below.The receiver buffer may be of a specified size B_(R).

FIG. 12 illustrates an example structure of an LLP. An LLP 1200 may becomprised of multiple frames 1203, which may be used to allow for thefair division of resources in a broadcast transmission stream.Accordingly, a first frame 1203 a of LLP 1200 may be transmitted at timeT1, while a second frame 1203 b may be transmitted at time T2 and athird frame 1203c is transmitted at time T3. The interval between thetransmission of each of frames 1203 may be defined by a parameterT_(INT) _(—) _(LLPF). T_(INT) _(—) _(LLPF) defines the amount of timebetween two consecutive frames, e.g. frames 1203 a and 1203 b, of aparticular LLP such as LLP 1200. During the time between frames of LLP1200, frames of other LLPs may be transmitted. Accordingly, transmissionbandwidth and resources may be divided amongst multiple LLPs.Furthermore, to avoid backlog and increase transmission and processingefficiency, a transmission protocol may adhere to the equation T_(OUT)_(—) _(LLP)≦T_(INT) _(—) _(LLPF). This equation allows for LLP frame1203 b, for example, to be consumed by the receiver prior to receivinganother LLP frame 1203 c. Additionally, a buffer size of LLP frame 1200may be required to be less than or equal to the buffer size of thereceiver. Again, such a rule may be implemented to reduce potential forbacklog and network slowdown. Alternatively or additionally, gaps may bescheduled for one or more LLP frame slots to allow for power saving. Forexample, LLP frame 1203 b may be transmitted 2*T_(INT) _(—) _(LLPF)after the transmission LLP frame 1203 a so that a receiver may powerdown during the slot provided T_(INT) _(—) _(LLPF) after thetransmission of LLP frame 1203 a.

In one or more configurations, LLP frames may vary in size from frame toframe. LLP frame size may be defined as BS_(LLPF). This frame size maybe, for example, the size of the largest LLP frame within an LLP. Areceiver may determine whether it has buffering capacity to receive anentire LLP based on the BS_(LLPF) and a time between two consecutiveframes of a LLP, indicated e.g. by T_(INT) _(—) _(LLPF) as describedabove. Additionally or alternatively, BS_(LLPF) may be required to beless than or equal to B_(R) for reception of a LLP.

FIG. 13 illustrates an example transmission protocol and structure inwhich LLP frames are transmitted in T2 frames of a DVB-T2 protocol. EachLLP frame 1301 encompasses a set of PLPs 1303 to which servicecomponents of a corresponding service are mapped. PLPs, as illustrated,may be defined by specified slots or slices and packet sizes in atransmission stream. For example, PLP 1 might be defined as occupyingthe 1^(st), 4^(th), 7^(th) and 10^(th) slices in a payload portion of aT2 frame. A PLP such as PLP 1303 c may occupy twice the number ofavailable slots or slices if, for example, PLP 1303 c is twice as largeas each of PLP 1303 a and 130 b. A remainder 1309 of each T2 frame 1307is apportioned to header data such as P1 and P2 and other LLP frames ofother services. During transmission of one or more of the other portions1309 of T2 frames 1307, a receiver interested in only the servicecorresponding to LLP frames 1301 may shut down various components forpower saving purposes. For example, a receiver may be awake to inspect aframe header including preamble symbols (e.g., P1 and P2) of the streamand shut down thereafter until relevant PLPs are to be received.Preamble symbols may be used during the initial signal scan for fastrecognition of a signal (e.g., T2), for which just the detection of P1is enough. Preamble symbols may also be used to identify the preambleitself as a specific type of preamble (e.g., a T2 preamble).Additionally, preamble symbols may be used to signal basic transmissionparameters that are needed to decode the rest of the preamble which canhelp during the initialization process. P1 may also be used to enablethe receiver to detect and correct frequency and timing synchronization.

Alternatively or additionally, a remainder of T2 frames 1307 notoccupied by PLPs 1303 might not include LLP frames for other servicesand may instead be configured to provide power conservation orprocessing time for the receiver. In the illustrated example, LLP frames1301 may be preceded by type ‘1’ PLPs or other types of PLPS. Type 1PLPs may generally refer to PLPs having one slice per frame. LLP frames1301 may be PLPs of type 2, which generally refers to PLPs having two ormore sub-slices per frame. The amount of time between each of LLP frames1301 may be T_(INT) _(—) _(LLPF) to provide sufficient time for areceiver to consume the previously received LLP frame.

FIG. 14 illustrates another example transmission protocol and structurein which LLP frames 1401 of a service alternate between carrying twoPLPs 1403 a and 140 b and a single PLP 1401 c. Accordingly, if each ofLLP frames 1401 is allotted 14 slices of a T2 frame 1405, PLPs 1403 aand 1403 b may each occupy 7 slices while PLP 1403 c may be given theentire allotment of 14 slices given its greater size. Further, assumingthat the sizes of PLPs 1403 a, 1403 b and 1403 c are equal to the sizesof PLPs 1203 a, 1203 b and 1203 c, respectively, a receiver operatingunder the transmission method and structure of FIG. 14 may require halfthe resources—e.g. in terms of buffer capacity—as the receiver operatingunder the system of FIG. 13 since half the amount of data is transmittedin any one of LLP frames 1401. However, depending on the frequency oftransmission of LLP frames 1401 as defined by T_(INT) _(—) _(LLPF), forexample, transmission of all LLP frames 1401 in a service may requiremore time than using the configuration of FIG. 13.

FIG. 15 illustrates an example signaling structure for a section of atable associating services or service components with an LLP. Asignaling structure may define the manner in which data is ordered andstructured in a transmission packet or stream. The signaling structure1500 may be defined using the following variables and information:

Table_id: An identifier for a table associating services with servicecomponents and a corresponding LLP. A table may include multiplesections, where each section corresponds to a service.

Section_syntax_indicator: The section_syntax_indicator is a 1-bit fieldwhich shall be set to a predefined value, for example to value “1”.

Section_Length: A 12-bit field that specifies a number of bytes of asection of the table, starting immediately following the section_lengthfield and including the cyclic redundancy check field CRC_(—)32. Asection generally refers to a section of a table (e.g., a programspecific information/service information table), wherein each sectionmay correspond to a different service.

Version_Number: A 5-bit field identifying the version of the table. Theversion number may be incremented by 1 when a change in the informationcarried within the table occurs. When the version number reaches a valueof 31, it wraps around to 0 upon incrementation.

Current_next_indicator: This may be a 1-bit indicator that, when set to“1” indicates that the currently applicable table is the current versionof the table (i.e., sub table). A value of “0,” however, indicates thatthe currently applicable table is the next version of the table.

Last_section_number: An 8-bit field specifying the number of the lastsection of the sub_table of which the section is a part. The lastsection number may further be used to determine the number of sectionswithin a table.

Identifier_loop_length: A 12 bit field indicating the length of theidentifier loop.

Identifier_type: Indicates the type of the associated identifier. Someexample types and their corresponding description are illustrated inFIG. 16.

LLP_Id: 16 bit identifier identifies a logical layer pipe within thenetwork (network specified by an identifier such as network_id).

CRC_(—)32: A 32-bit cyclic redundancy checksum (CRC) that contains theCRC value that gives a zero output of the registers in the decoder. A32-bit CRC decoder operates at bit level and consists of 14 adders+and32 delay elements z(i). The input of the CRC decoder is added to theoutput of z(31), and the result is provided to the input z(0) and to oneof the inputs of each remaining adder. The other input of each remainingadder is the output of z(i), while the output of each remaining adder isconnected to the input of z(i+1), with i=0, 1, 3, 4, 6, 7, 9, 10, 11,15, 21, 22 and 25 (as illustrated in FIG. 23). This is the CRCcalculated with the polynomial:x³²+x²⁶+x²³+x²²+x¹⁶+x¹²+x¹¹+x¹⁰+x⁸+x⁷+x⁵+x⁴+x²+x+1

At the input of the CRC decoder, bytes are received. Each byte isshifted into the CRC decoder one bit at a time, with the mostsignificant bit (msb) first, i.e. from byte 0x01 (the last byte of thestartcode prefix). First the seven “0”s enter the CRC decoder, followedby the one “1”. Before the CRC processing of the data of a section theoutput of each delay element z(i) is set to its initial value “1”. Afterthis initialization, each byte of the section is provided to the inputof the CRC decoder, including the four CRC_(—)32 bytes. After shiftingthe last bit of the last CRC_(—)32 byte into the decoder, i.e. into z(0)after the addition with the output of z(31), the output of all delayelements z(i) is read. In case of no errors, each of the outputs of z(i)is to be zero. At the CRC encoder the CRC_(—)32 field is encoded withsuch value that this is ensured.

Associated services and service components may be identified in avariety of ways including by IP address, which can be either IPv4 orIPv6, URI, a private type of identifier and the like. For example, aservice identified by IPv4 may include an IPv4 source address, e.g.IPv4_src_addr, and an IPv4 destination address, e.g. IPv4_dst_addr.

FIG. 17 illustrates an example broadcast data model that uses LLPs toassociate a service component of a broadcast service with acorresponding PLP. The data model 1700 may include at least two layers,a broadcast layer 1701, e.g. an application layer such as an OMA-BCASTlayer, and a signaling layer 1703, e.g. a physical layer. The signalinglayer 1703 may be included in any layer and is not restricted to thephysical layer. The broadcast layer 1701 may comprise parametersassociated with the content 1705, the service 1707, access 1709,scheduling and a service component associated with the service. Forexample, content information may specify a version number, a validityrange, a global content identifier and an associated service identifier.The service component, in one or more arrangements, may be expressedaccording to session description protocol (SDP) 1713. Serviceinformation 1707 may similarly include a version number, validity range,identifier as well as content protection information and service type.Each session description protocol 1713 entry may correspond to a servicecomponent of service 1707. In the illustrated example, LLP 1715 isdirectly associated or linked to service component 1713, mapping servicecomponent 1713 to PLP 1717. In one or more configurations, sessiondescription protocol 1713 may include an LLP identifier parameterspecifying an LLP linked to a corresponding PLP 1717 of service 1707.

LLP 1715 and PLP 1717 may be defined and conveyed in signaling layer1703, e.g. a physical layer. Although LLP 1715 is illustrated as beinglinked to a single PLP 1717, LLP 1715 may similarly be linked tomultiple PLPs as described herein. PLP 1717 may include a PLP identifierand be linked to information such as a number of frames or a number ofsuper frames—defined e.g. as a group of frames—making up the PLP 1717, afirst frame identifier, a frame interval, cell identifier, networkidentifier, a broadcast system identifier and a frequency. A cellidentifier defines a geographic section or cell within a broadcastnetwork. A cell's coverage area within the network may include one ormore frequencies.

FIG. 18 illustrates an example data model 1801 where an adaptationlayer—e.g. an L2 layer in the OSI data model—1803 is used to define LLP1805 and its association with PLP 1807. Rather than adapting a signalinglayer to include LLP information as described in FIG. 17, an associationbetween service 1809 and PLP 1807 is specified through LLP 1805 inadaptation layer 1803. Additionally, instead of a direct association orlink between service component 1811 and LLP 1805, as shown in FIG. 17,LLP 1805 is linked to service 1809 and thereby indirectly associatedwith service component 1811, by virtue of service 1809's identificationof and association with service component 1811.

FIG. 19 illustrates an example data model whereby service component 1911is associated with LLP 1905 through a mapping component 1907 inadaptation layer 1903. In particular, the mapping 1907 may include an IPsource address and IP destination address of the service component 1911.Additionally, mapping 1907 may specify an LLP identifier correspondingto LLP 1905. LLP 1905 may then be associated with one or more PLPs suchas PLP 1907 to which service component 1911 is mapped or to be mapped.Each service component in a service may be associated with a uniquemapping while all mappings for those service components may beassociated with the same LLP 1905. This allows a single LLP to beconstructed for mapping service components to PLPs in a transmissionstream in the configuration of FIG. 19.

FIG. 20 illustrates an example signaling structure for providing anassociation between LLPs, PLPs and related parameters. LLP associationsmay be defined in a section of a transmission and may have a specifiednumber of LLPs. The size of the section may correspond to the number ofLLPs. Each LLP may be associated with a set of PLPs, a number of PLPs inthe set defined by, for example, the variable PLP_loop_length. Each LLPmay further be identified by an identifier such as LLP_ID. The timebetween LLP frames in a transmission may be represented by T_INT_LLPFwhile the size of the largest LLP frame within an LLP may be specifiedby BS_LLPF.

FIG. 21 illustrates an example method by which a user may discover andaccess a service and its associated service components. In step 2100, areceiving device such as a mobile terminal or set top box may seek orotherwise detect a broadcast signal. The broadcast signal may advertisemultiple services that each includes one or more service components.Once the broadcast signal has been detected and identified, thereceiving device may then receive broadcast information signalsassociated with the services or service components available in thebroadcast in step 2105. For example, layer 1 and layer 2 signaling maybe received. Layer 1 signaling may include, for instance, electronicservice guide information while layer 2 may include an adaptation layerincluding logical layer pipe data. In step 2110, service guideinformation may be sought and accessed by the receiver based on thebroadcast information signals received in step 2105. In step 2115, thereceiver may subsequently identify logical layer pipe identifiers forservices and service components available in the broadcast. This may beaccomplished by examining service guide information or a serviceinformation table provided in the broadcast information signal.

In step 2120, using the logical layer pipe identifiers, the receiver maydetermine—and possibly display—available or receivable services. Thedetermination may be performed by inspecting a receiver buffer storingprogramming and service information for parameters associated with eachlogical layer pipe identifier. The parameters may include, for example,descriptions, identifiers, service components and the like of servicesavailable in the broadcast network. In one example, LLP and serviceassociations may be stored in a PSI/SI table. In step 2125, the receivermay determine a selection of a service made—for example by a user. Instep 2130, the receiver may discover or otherwise determine physicallayer pipes to which service components associated with the selectedservice are mapped. As described herein, the logical layer pipeassociated with a particular service or service component identifies thephysical layer pipes to which the service components are mapped.Accordingly, the receiver may identify the appropriate PLPs using theLLP. Once the corresponding PLPs have been identified, the receiver maybegin receiving, accessing and consuming the service and the associatedservice components through their respective PLPs in step 2135. That is,the receiver may determine which frames and/or slices are assigned to aparticular PLP configured to carry the service components. In one ormore configurations, the receiving device may selectively access servicecomponents of a service by identifying and accessing specific PLPscorresponding to desired components. In one example, a service componentmay be defined according to a session description protocol (SDP) formatthat includes an identifier specifying the PLP to which it isassociated. Thus, a receiving device may be able to determine aparticular PLP for accessing a specific service component.

In one or more configurations, a receiver may determine which servicecomponents of a service are desired. For example, if a receiver orterminal is not capable of rendering high definition content, thereceiver might only access standard definition content data of a highdefinition content service. In particular, the receiver might not accesshigh definition content data due to its inability to render or processsuch data. Accordingly, the receiver might only identify the PLP(s)associated with desired service components, rather than all servicecomponents.

FIG. 22 illustrates an example method for broadcasting services andassociated service components using LLPs and PLPs. In step 2200, priorto or concurrently with broadcasting the availability of services, as instep 2205, the broadcast system may define or create a transmissionsignaling structure described herein by mapping service components orservices with corresponding PLPs through the use of LLPs. For example, anumber of PLPs may first be defined for carrying service components of aservice. The number of PLPs may be depend on whether service componentsneed to be shared or treated differently, e.g. in terms of errorcorrection or detection protocols and the like. LLPs may then beconstructed to correlate the PLPs to the service components or services.In step 2205, the system may broadcast the availability of servicesthrough a network to one or more network devices. The broadcast mayinclude service information such as an electronic service guide. Theelectronic service guide or other service information may allow networkdevices to identify the LLPs associated with each service or servicecomponent advertised in the broadcast. The LLPs may further facilitatethe identification of PLPs carrying specified service components orservices. A receiving device may thus subscribe to a desired service andaccess the service as well as associated service components throughdiscovering the LLPs and PLPs associated therewith. In step 2210, thebroadcast system may begin or continue to broadcast the availableservices and service components in accordance with the LLP and PLPsignaling structure. From a receiving device's perspective, service andservice component information may be received and accessed uponidentifying the appropriate LLPs and PLPs associated therewith.

In one example embodiment, a method according to aspects describedherein may include identifying a first service component and a secondservice component associated with a broadcast service; generating alogical layer pipe; and mapping the first service component to a firstphysical layer transmission channel and the second service component toa second physical layer transmission channel through the logical layerpipe. Additionally or alternatively, the method may further includeassociating the logical layer pipe to the broadcast service, generatinga first mapping component for the first service component and linkingthe first service component to the logical layer pipe through the firstmapping component, and/or generating a second mapping component for thesecond service component and linking the second service component to thelogical layer pipe through the second mapping component.

In another example embodiment, one or more computer readable media maystore computer readable instructions that, when executed, cause anapparatus to identify a first service component and a second servicecomponent associated with a broadcast service, generate a logical layerpipe, and map the first service component to a first physical layertransmission channel and the second service component to a secondphysical layer transmission channel through the logical layer pipe.Additionally or alternatively, the computer readable instructions, whenexecuted, may further cause the apparatus to link the logical layer pipeto the broadcast service, generate a first mapping component for thefirst service component and link the first service component to thelogical layer pipe through the first mapping component, generate asecond mapping component for the second service component and link thesecond service component to the logical layer pipe through the secondmapping component, generate a first mapping component for the firstservice component and link the first service component to the logicallayer pipe through the first mapping component, generate a secondmapping component for the second service component and link the secondservice component to the logical layer pipe through the second mappingcomponent, and/or transmit a broadcast signal to a receiving device,wherein the broadcast signal includes identification information of thelogical layer pipe.

In yet another example embodiment, an apparatus according to aspectsdescribed herein may include means for receiving a broadcast signalcomprising a first broadcast service associated with a first servicecomponent, means for determining a logical layer pipe associated withthe first broadcast service, means for determining a first physicallayer transmission channel to which the first service componentassociated with the first broadcast service is mapped based on thelogical layer pipe, wherein the first physical layer transmissionchannel is different from the logical layer pipe, and means foraccessing the first service component for the first broadcast servicethrough the first physical layer transmission channel. The means forreceiving a broadcast signal may include a receiver buffer. Additionallyor alternatively, the broadcast signal may include a second broadcastservice sharing the service component with the first broadcast serviceand the apparatus may further include means for determining a secondlogical layer pipe associated with the second broadcast service, meansfor determining that the first service component is mapped to the firstphysical layer transmission channel using the second logical layer pipe,and means for accessing the first service component for the secondbroadcast service through the first physical layer transmission channel.Further, the apparatus may include means for determining that the firstbroadcast service includes a plurality of service components, and meansfor determining one or more service components of the plurality ofservice components to access based on a receiver capability.

It should be understood that any of the method steps, procedures orfunctions described herein may be implemented using one or moreprocessors in combination with executable instructions that cause theprocessors and other components to perform the method steps, proceduresor functions. As used herein, the terms “processor” and “computer”whether used alone or in combination with executable instructions storedin a memory or other computer-readable storage medium should beunderstood to encompass any of various types of well-known computingstructures including but not limited to one or more microprocessors,special-purpose computer chips, field-programmable gate arrays (FPGAS),controllers, application-specific integrated circuits (ASICS),combinations of hardware/firmware/software, or other special orgeneral-purpose processing circuitry.

The methods and features recited herein may further be implementedthrough any number of computer readable media that are able to storecomputer readable instructions. Examples of computer readable media thatmay be used include RAM, ROM, EEPROM, flash memory or other memorytechnology, CD-ROM, DVD or other optical disk storage, magneticcassettes, magnetic tape, magnetic storage and the like.

Additionally or alternatively, in at least some embodiments, the methodsand features recited herein may be implemented through one or moreintegrated circuits (ICs). An integrated circuit may, for example, be amicroprocessor that accesses programming instructions or other datastored in a read only memory (ROM). In some such embodiments, the ROMstores programming instructions that cause the IC to perform operationsaccording to one or more of the methods described herein. In at leastsome other embodiments, one or more the methods described herein arehardwired into an IC. In other words, the IC is in such cases anapplication specific integrated circuit (ASIC) having gates and otherlogic dedicated to the calculations and other operations describedherein. In still other embodiments, the IC may perform some operationsbased on execution of programming instructions read from ROM or RAM,with other operations hardwired into gates and other logic of IC.Further, the IC may output image data to a display buffer.

Although specific examples of carrying out the invention have beendescribed, those skilled in the art will appreciate that there arenumerous variations and permutations of the above-described systems andmethods that are contained within the spirit and scope of the inventionas set forth in the appended claims. Additionally, numerous otherembodiments, modifications and variations within the scope and spirit ofthe appended claims will occur to persons of ordinary skill in the artfrom a review of this disclosure.

We claim:
 1. A method comprising: receiving a broadcast signalcomprising a first broadcast service associated with a first servicecomponent; receiving a service association table that includesassociations between the first broadcast service and a plurality ofphysical layer transmission channels that are configured to carry thefirst broadcast service; identifying, based on the service associationtable, the plurality of physical layer transmission channels that areassociated with the first broadcast service; determining a firstphysical layer transmission channel carrying the first service componentfrom the plurality of physical layer transmission channels; determining,from the service association table, one or more buffer parameters forthe first broadcast service; and accessing the first service componentfor the first broadcast service through the first physical layertransmission channel.
 2. The method of claim 1, wherein the firstbroadcast service is further associated with a second service component,each of the first and second service components being mapped to adifferent one of the plurality of physical layer transmission channelsand wherein the method further comprises: determining a second physicallayer transmission channel to which the second service component ismapped using the service association table; and accessing the secondservice component for the first broadcast service through the secondphysical layer transmission channel.
 3. The method of claim 2, furthercomprising determining that the first service component and the secondservice component correspond to different layers of a scalable videocodec.
 4. The method of claim 2, further comprising applying a firsterror correction function to the first service component and a seconderror correction function different from the first error correctfunction to the second service component.
 5. The method of claim 1,wherein the broadcast signal comprises a second broadcast servicesharing the first service component with the first broadcast service andwherein the method further comprises: identifying, based on the serviceassociation table, that the second broadcast service is associated withthe first service component; determining that the first servicecomponent is mapped to the first physical layer transmission channelusing the service association table; and accessing the first servicecomponent for the second broadcast service through the first physicallayer transmission channel.
 6. The method of claim 1, furthercomprising: determining that the first broadcast service includes aplurality of service components; and determining one or more servicecomponents of the plurality of service components to access based on areceiver capability.
 7. The method of claim 1, wherein the firstphysical layer transmission channel corresponds to a plurality ofbroadcast frames in a transmission stream.
 8. The method of claim 7,wherein the first physical layer transmission channel is further definedby a set of transmission slices in the plurality of broadcast frames. 9.The method of claim 1, wherein the one or more buffer parameterscomprise a buffer size parameter indicating a required memory forbuffering a frame of the first broadcast service or a time parameterindicating a maximum allowed time to consume the buffered frame.
 10. Oneor more non-transitory computer readable media storing computer readableinstructions that, when executed, cause an apparatus to: receive abroadcast signal comprising a first broadcast service associated with afirst service component; receive a service association table thatincludes associations between the first broadcast service and aplurality of physical layer transmission channels that are configured tocarry the first broadcast service; identify, based on the serviceassociation table, the plurality of physical layer transmission channelsthat are associated with the first broadcast service; determine a firstphysical layer transmission channel carrying the first service componentfrom the plurality of physical layer transmission channels; determine,from the service association table, one or more buffer parameters forthe first broadcast service; and access the first service component forthe first broadcast service through the first physical layertransmission channel.
 11. The one or more non-transitory computerreadable media of claim 10, wherein the first broadcast service isfurther associated with a second service component, each of the firstand second service components being mapped to a different one of theplurality of physical layer transmission channels and wherein thecomputer readable instructions, when executed, further cause theapparatus to: determine a second physical layer transmission channel towhich the second service component is mapped using the serviceassociation table; and access the second service component for the firstbroadcast service through the second physical layer transmissionchannel.
 12. The one or more non-transitory computer readable media ofclaim 11, wherein the computer readable instructions, when executed,further cause the apparatus to determine that the first servicecomponent and the second service component correspond to differentlayers of a scalable video codec.
 13. The one or more non-transitorycomputer readable media of claim 11, wherein the computer readableinstructions, when executed, further cause the apparatus to apply afirst error correction function to the first service component and asecond error correction function different from the first error correctfunction to the second service component.
 14. The one or morenon-transitory computer readable media of claim 10, wherein thebroadcast signal comprises a second broadcast service sharing the firstservice component with the first broadcast service and wherein thecomputer readable instructions, when executed, further cause theapparatus to: identify, based on the service association table, that thesecond broadcast service is associated with the first service component;determine that the first service component is mapped to the firstphysical layer transmission channel using the service association table;and access the first service component for the second broadcast servicethrough the first physical layer transmission channel.
 15. The one ormore non-transitory computer readable media of claim 10, wherein thecomputer readable instructions, when executed, further cause theapparatus to: determine that the first broadcast service includes aplurality of service components; and determine one or more servicecomponents of the plurality of service components to access based on areceiver capability.
 16. The one or more non-transitory computerreadable media of claim 10, wherein accessing the first servicecomponent includes receiving the first service component.
 17. Anapparatus comprising: a processor; and memory storing computer readableinstructions that, when executed, cause the apparatus to: receive abroadcast signal comprising a first broadcast service associated with afirst service component; receive a service association table thatincludes associations between the first broadcast service and aplurality of physical layer transmission channels that are configured tocarry the first broadcast service; identify, based on the serviceassociation able, the plurality of physical layer transmission channelsthat are associated with the first broadcast service; determine a firstphysical layer transmission channel carrying the first service componentfrom the plurality of physical layer transmission channels; determine,from the service association table, one or more buffer parameters forthe first broadcast service; and access the first service component forthe first broadcast service through the first physical layertransmission channel.
 18. The apparatus of claim 17, wherein the firstbroadcast service is further associated with a second service component,each of the first and second service components being mapped to adifferent one of the plurality of physical layer transmission channelsand wherein the computer readable instructions, when executed, furthercause the apparatus to: determine a second physical layer transmissionchannel to which the second service component is mapped using theservice association table; and access the second service component forthe first broadcast service through the second physical layertransmission channel.
 19. The apparatus of claim 18, wherein thecomputer readable instructions, when executed, further cause theapparatus to determine that the first service component and the secondservice component correspond to different layers of a scalable videocodec.
 20. The apparatus of claim 18, wherein the computer readableinstructions, when executed, further cause the apparatus to apply afirst error correction function to the first service component and asecond error correction function different from the first error correctfunction to the second service component.
 21. An apparatus comprising: aprocessor; and memory storing computer readable instructions that, whenexecuted, cause the apparatus to: identify a first service component anda second service component associated with a broadcast service; generatean association section that includes a first association linking thefirst service component with a first physical layer pipe that istransmitted in a plurality of time slices, a second association linkingthe second service component with a second physical layer pipe that istransmitted in the plurality of time slices, and one or more bufferparameters; wherein the one or more buffer parameters include: (a) abuffer size parameter indicating a maximum size of the plurality of timeslices, or (b) a time parameter indicating an interval of time betweenthe plurality of time slices and another plurality of time slices thatinclude physical layer pipes linked to the first service component andthe second service component; and transmit the association section.